Preparation and thermoelectric properties of p-type (Ga2Te3)x–(Bi0.5Sb1.5Te3)1−x (x = 0–0.2) alloys prepared by spark plasma sintering

p-Type (Ga2Te3)x–(Bi0.5Sb1.5Te3)1−x (x = 0–0.2) alloys were prepared by spark plasma sintering technique, and the effect of gallium telluride (Ga2Te3) on the thermoelectric properties was experimentally determined. Measurements have shown that the electrical conductivities of (Ga2Te3)x–(Bi0.5Sb1.5Te3)1−x are improved and thermal conductivities reduced after the introduction of Ga2Te3 in the Bi0.5Sb1.5Te3 alloy without noticeable loss of Seebeck coefficient. The maximum thermoelectric figure of merit ZT of 1.0 is obtained with molar fraction x = 0.1 at 335.5 K, being approximately two times that of the Bi0.5Sb1.5Te3 at the corresponding temperature, thus proving that (Ga2Te3)x–(Bi0.5Sb1.5Te3)1−x (x = 0–0.2) alloys are to be a promising material for application.